BitTorrent network topology active measurement method

Peer-to-peer (P2P) network topology measurement is the foundation for research of p2p network sharing behavior pattern and network resources dynamic distribution. To BitTorrent (BT) network, we present an active measurement method of network topology. Firstly, using seed crawler get entire BT network´s seeds, then through analyzing every seed to get tracker servers´ information, after that, BT crawler inquire every track server to get peers´ information, and now, we achieve BT network topology measurement. At the end, an example is given and proving the validity of this method.